1. yes, however they may require prior authorization and evidence of medical necessity
2. yes, always need ICD-10 codes (typically this will be a dementia, neurodevelopmental, or somatoform code)
although physicians can use 96101-96103 in practice these codes are meant for psychologists doing testing. It is highly unlikely that a psychiatrist in private practice would be doing an MMPI-2, PAI, WAIS, Rorschach etc or other tests that fit under these codes in order to bill for them. If your private practice had psychometrists and psychologists then of course you can bill for these. 90785 is just an interactive complexity code, you add it on to a psychotherapy code on a 90792.
You can only use it for the following situations:
1. The need to manage maladaptive communication (related to, e.g., high anxiety, high reactivity, repeated questions, or disagreement) among participants that complicates delivery of care.
2. Caregiver emotions/behavior that interfere with implementation of the treatment plan.
3. Evidence/disclosure of a sentinel event and man dated report to a third party (e.g., abuse or neglect with report to state agency) with
initiation of discussion of the sentinel event and/or report with patient and other visit participants.
4.Use of play equipment, physical devices, interpreter or translator to overcome significant language barriers.
Last I checked, medicare only reimbursed $8 for 90785 and private insurance a little more, so while you should use it when appropriate, it's not really much of a game changer